Federal prosecutors say six people have pleaded guilty to charges stemming from an investigation into a massive software piracy scheme that began in Kansas City and involved $100 million worth of illegitimate software.

Tammy Dickinson, U.S. attorney for the western district of Missouri, said Thursday the case is among the largest software piracy schemes prosecuted by the Justice Department. She says the case involved more than $100 million worth of stolen or counterfeit software products, including thousands of access codes for Microsoft and Adobe Systems products.

Authorities also confiscated about $20 million in assets, including real estate, from six defendants in Missouri, Washington state, Maryland, Colorado and Nevada.

The prosecutor's office says the defendants pleaded guilty to various charges, including conspiracy to defraud the U.S. The investigation is ongoing.

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